ABSTRACT
The aim of the NIRP research project was to study the three programmes as they were actually operating, and to make the evaluation as unintrusive as possible. The organization of the programmes differed considerably and the daily management of the programmes therefore placed restraints on the evaluation, as is usual in post facto studies. It was not possible to use an identical study design in the three studies. Instead the designs were adapted to the particular conditions at each of the programmes. This chapter presents a brief description of the different constraints in each case and the designs that were finally chosen, together with a discussion of possible confounding variables. Except for some minor variations, the outcome measures or indicators are the same in each of the studies. They are discussed in the last section of this chapter.
